La Guardia Airport is such a tangled patchwork of terminals, gates and runways that it should be torn down and replaced, the Port Authority’s top honcho said yesterday.

“La Guardia should not be the gateway for domestic flights into New York City,” PA Director Chris Ward told city business leaders at a Crain’s New York Business breakfast. “It should fundamentally be torn down and rebuilt again.”

But Ward was quick to add that there is no funding available in the foreseeable future to rebuild the aging airstrip. As The Post reported last year, the PA cut $1 billion from its capital plan to rebuild La Guardia’s Central Terminal Building because of budget shortfalls.

“The capital necessary to rebuild La Guardia is not there. But the planning capacity is and we’re working with the consulting industry to reimagine what La Guardia could, in fact, look like when it gets completely rebuilt,” Ward told reporters after his speech.

Ward said any rebuilding would be phased in over time.

“La Guardia was built over decades. It’s not the kind of integrated aviation facility that the 21st century really demands. On top of that, we’ve layered in post-9/11 security. Because of that, you have an experience for the air traveler that is unnecessarily chaotic, which is difficult to manage,” said Ward.

“I think, candidly, over time, building piece by piece, La Guardia has to be completely redone.”

While planning for a reconstruction is under way, the PA’s next round of capital spending won’t be up for grabs until 2017, agency officials said.

La Guardia was opened as the city’s first municipal airport in 1939. The PA assumed control in 1947 and is operating La Guardia under a lease with the city that runs through 2050.

With the economic downturn, the PA suffered a dramatic drop in both bridge and tunnel tolls and airport landing fees, forcing the agency to cut $1 billion from capital projects at La Guardia and another $1 billion from Newark Liberty Airport.

La Guardia’s Central Terminal Building was last renovated in 1964, and the airport served 23 million travelers last year.

The PA would be in talks with airlines using La Guardia about the potential for sharing costs of any future rebuilding, Ward said.